I really want to find this book again. I had it back in the seventies, the story was complex, surreal, competing realities type.
The cover showed one figure (I think), anyway, their neck was a platform, their head consisted of two small humanoid figures dancing on that platform.
There were I believe, 7 entities in this "station" which was outside of normal reality. And each one completely controlled reality with their section of the station and whatever part of the outside they could manage.
There was also the sense of hypothesis exploding sequences where each time you think you have what is happening figured out, everything changes. Like in The Magus, and/or The Illuminatus Trilogy.
Each one of these principal characters maintained their "bodies" in whatever manner they chose. The cover figure, whose head was the two small dancing figures on his platform like neck, was one of the principal characters.
The whole effect was so bizarre that I think if anybody else has this book or remembers it's name or author or anything, I will be able to trace it down.